That isn't a good argument for price decrease. Different nations have different attributes. People bitch and moan about panzershrek being super costly but i don't see anyone bating an eyelid at UKF's infantry's section useless and costly gammon bomb or the cheap but useless PIAT.
useless piat if you don't attack ground or use them on light vehicle gamon is good think about it same as penal satchels with the added bonus of stunning tank and dealing high damage
Btw panzer sherck cost 60 each why should they cost 90 on sturm would it be fair if piat costed more for Sapper or bazoka for RE